Number of vendors represents more than ten percentage of purchases.

No definition available.

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- Definition

Percentage of purchases during year.

+ References

No definition available.

+ Details

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

+ Details

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- Definition

Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Concentrations of Credit Risk - Additional Information (Detail)	12 Months Ended
	Sep. 30, 2024 USD ($) Vendor	Sep. 30, 2023 USD ($)	Sep. 30, 2022
Concentration Risk [Line Items]
Restricted cash	$ 3,009,000	$ 3,132,000
Outstanding letters of credit to be collateralized by amounts on deposit	3,000,000	3,100,000
Allowance for doubtful accounts	$ 0	$ 0
Number of vendors represents more than ten percentage of purchases \| Vendor	2
AAR {Member]
Concentration Risk [Line Items]
Percentage of purchases during year	18.00%
Standard Aero Holdings, Inc. [Member]
Concentration Risk [Line Items]
Percentage of purchases during year	11.00%
Sales Revenue, Net [Member] \| American Airlines Inc. [Member] \| Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	23.00%	45.00%
Sales Revenue, Net [Member] \| United [Member] \| Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	97.00%	73.00%	48.00%